This disclosure relates generally to connections between trusses and non-load bearing walls.
Interior non-load bearing walls are typically framed approximately ½ inch to ¾ inch below the load bearing components. Such components take the form of floor joist, floor trusses, roof trusses, etc. This gap allows the load bearing components to deflect under the pre-designed loads.
If the non-load bearing walls are built flush to the underside of the load bearing components, they can essentially become load bearing or quasi-load bearing. Consequently, the truss or joist is not going to react and deflect in the same manner as designed due to the additional load bearing. Furthermore, loads would then be transferred to structural components that are not designed to handle the loads. The latter would typically result in dips in floors, the cracking of finished work and actual failure of a component.
Of course, the non-load bearing walls still require bracing against lateral movement which is typically the goal of the fastening between the non-load bearing wall and the truss or other load bearing structure.